Queries, in the form of SELECT
statements, perform all the lookup operations in the database.
Tuning these statements is a top priority, whether to achieve
sub-second response times for dynamic web pages, or to chop
hours off the time to generate huge overnight reports.

MySQL Cluster supports a join pushdown optimization whereby a
qualifying join is sent in its entirety to MySQL Cluster data
nodes, where it can be distributed among them and executed in
parallel. For more information about this optimization, see
Conditions for NDB pushdown joins,